I don't
work at the CBO.
And the CBO is non-partisan.
The goal is not to make a 100% accurate down-to-the-cent prediction, and the CBO explicitly acknowledges that they don't account for macroeconomic trends -- though they do point out that the subsequent population growth should encourage GDP growth.
It's basically just a policy guideline, which gives an idea of likely outcomes.
Normally the CBO only does 10 years. However, that would distort many factors, including the income from penalties, and how RPI's won't qualify to become LPR's for 10 years.
Actually, passing immigration reform is a good way for the Republican Party to get on the good side of Hispanics and other immigrant-heavy groups, and minorities (especially Hispanics) can only benefit from both parties competing for their votes.
"The Truth" is that 87% of Republicans are white; 71% of Hispanics voted for Obama; 93% of blacks voted for Obama, whites will be a minority in the US about 30 years -- and in California, about 1 year.
Republicans need to stop vilifying illegal immigrants
now, and start appealing to minority voters, or else they will spend decades losing power and receding into the political wilderness. Merely assuming that all illegal immigrants will vote Democratic by default is not going to help with that process.
Or, to make it more explicit: My interest in immigration reform is not partisan. I'd much rather have Republicans pass a good bill, and get credit for it, than to have the Democrats score a few points. I've been pretty consistent on this point on this forum.
Is that enough "truth" for you?